It's not a complete redesign by YouTube, its just the search bar which has become a more prominent item of the homepage. It's now right there at the left top corner and it's slightly bigger than the old one.

The changes to top of the homepage aren't very big. The new design is more 'smooth' so to say. And the focus has definitly changed. In stead of promoting the different tabs to videos, shows, community and channels the focus is on the search bar. You want to search not click now.

Before

After

Where Google is trying to get more social with iGoogle Youtube seems to have gone the opposite way. The tab 'community' for example is completely removed.

YouTube has always been a search engine in a way, a video search engine. But now they really have gone towards search. And as Gerg Sterling very well explained in is article "Augmented Reality’ Is Also A Form Of Search" on Searchengineland yesterday, there is more to search than just the search bar. But YouTube believes, rightfully I think, that the search bar will help them get more traffic.

Comments (2)

First of all, your before and after screenshots should be the other way around.

Much of the social stuff around YouTube is going on outside the website. You see references to YouTube on other websites, in newspapers, magazines etc. Considering the tremendous amount of videos on YouTube, search is the way to go if you're looking for specific (kinds of) videos. So find and watch videos fast and get social from there on.

About the community tab: I won't miss it. YouTube doesn't need a 'community' tab. YouTube IS the community :-)